To some Iowans, they’re just oblong shells that won’t be missed. But to biologists, the death of two species of Iowa mussels is a sign that our state’s waters have never been filthier.

This is the Iowa Environmental Focus.

The US Fish and Wildlife Service may soon add the sheepnose and spectaclecase mussels to the endangered species list. Polluted water has reduced their populations by more than 50 percent.

Iowa’s waters are the dirtiest they’ve been in 14 years of record keeping, according to a new DNR study. In 2010, at least 572 bodies of water in the state were termed polluted – a six percent increase from 2008, the study found.

But we can work to clean up Iowa’s act. By reducing farm runoff and factory pollution, we can help make Iowa’s waters cleaner for fishing, recreation and drinking.